Various methods are known for the production of flavine nucleotides. Thus, mention may be made, of, for instance, the method disclosed in JP-A-132898/84 which uses a microorganism belonging to the genus Corynebacterium or Brevibacterium and capable of forming adenosine-5'-triphosphate (ATP) from an ATP precursor, a phosphate donor and an energy donor and further capable of forming FAD from FMN and ATP, and the method disclosed in JP-A-138988/90 which uses a microorganism belonging to the genus Corynebacterium or Brevibacterium and harboring a recombinant DNA which contains a DNA fragment carrying the genetic information relevant to the synthesis of FMN or FAD as derived from a microorganism belonging to the genus Corynebacterium or Brevibacterium (the term "JP-A" used herein means an unexamined published Japanese patent application).
Further it is known that, in microorganisms belonging to the genus Brevibacterium, the flavokinase (FK) activity for the formation of FMN from riboflavine (FR) and ATP and the flavine adenine dinucleotide synthetase (FADS) activity for the formation of FAD from FMN and ATP occur on one and the same protein Journal of Biological Chemistry, 261, 16169-16173 (1986)!.
However, no methods are known for using microorganisms belonging to the genus Escherichia, Enterobacter or Pseudomonas and harboring a recombinant DNA which contains a DNA fragment carrying the genetic information relevant to the synthesis of FMN and/or FAD.